Display substrate and preparation method thereof, and display apparatus

ABSTRACT

A display substrate, a preparation method thereof and a display apparatus. The display substrate comprises a substrate, multiple pixel units arranged on the substrate and a color filter layer arranged on the pixel unit, wherein the color filter layer comprises color optical filters of different colors and a touch control structure layer arranged between the color optical filters of different colors; the touch control structure layer comprises a touch control connection electrode, a first coating protective layer covering the touch control connection electrode and a touch control electrode arranged on the first coating protective layer, the touch control electrodes comprise a first touch control electrode and a second touch control electrode, and at least one of the first touch control electrode and the second touch control electrode is connected with the touch control connection electrode through a via hole penetrating through the first coating protective layer.

CROSS-REFERENCE TO RELATED APPLICATION

The present application claims the priority of Chinese PatentApplication No. 202011145176.8 filed to the CNIPA on Oct. 23, 2020, thecontent of which is hereby incorporated by reference.

TECHNICAL FIELD

The present disclosure relates to, but is not limited to, the field ofdisplay technology, and particularly relates to a display substrate, apreparation method thereof, and a display apparatus.

BACKGROUND

An Organic Light Emitting Diode (OLED) is an active light emittingdisplay device, and has advantages of self-emission, wide view, highcontrast, low power consumption, extremely high response speed, etc.With the continuous development of display technology, the OLEDtechnology is increasingly applied in flexible display devices.

The Flexible Multi-Layer On Cell (FMLOC) and CF on Encapsulation (COE)technologies integrate the functions of touch control and optical filterinto a whole, forming a multi-functional layer stacked display substratestructure.

SUMMARY

The following is a summary of the subject matter described in detail inthe present disclosure. This summary is not intended to limit theprotection scope of the claims.

In a first aspect, the present disclosure provides a display substrate,which includes a substrate, multiple pixel units arranged on thesubstrate, and a color filter layer arranged on the pixel units, whereinthe color filter layer includes color optical filters of differentcolors and a touch control structure layer arranged between the coloroptical filters of different colors; the touch control structure layerincludes a touch control connection electrode, a first coatingprotective layer covering the touch control connection electrode and atouch control electrode arranged on the first coating protective layer,wherein the touch control electrode includes a first touch controlelectrode and a second touch control electrode, and at least one of thefirst touch control electrode and the second touch control electrode isconnected with the touch control connection electrode through a via holepenetrating through the first coating protective layer.

In some exemplary embodiments, the touch control electrode includes afirst metal layer and a second metal layer arranged on the first metallayer, wherein the orthographic projection of the second metal layer onthe substrate coincides with the orthographic projection of the firstmetal layer on the substrate.

In some exemplary embodiments, the touch control electrode furtherincludes a third metal layer, wherein the first metal layer is arrangedon the third metal layer, and the construction material of the thirdmetal layer includes titanium.

In some exemplary embodiments, the reflectivity of the second metallayer is less than a first reflectivity, and the construction materialof the second metal layer includes molybdenum oxide.

In an exemplary embodiment, the first reflectivity is 17%.

In some exemplary embodiments, the thickness of the touch controlelectrode is 300 nm to 400 nm.

In some exemplary embodiments, the thickness of the second metal layeris 35 nm to 70 nm.

In some possible embodiments, the thickness of the color filter layer is2 microns to 3 microns.

In some exemplary embodiments, the thickness of the touch controlconnection electrode is 150 nm to 300 nm.

In some exemplary embodiments, the thickness of the first coatingprotective layer is 1.5 microns to 2.5 microns.

In some exemplary embodiments, the pixel unit includes multiplesub-pixels, and each sub-pixel includes a driving structure layer, afirst planarization layer, a first electrode, a pixel definition layer,an organic light emitting layer, a second electrode, and anencapsulation layer. The driving structure layer is arranged on thesubstrate, and a driving structure layer in each sub-pixel includes afirst thin film transistor.

The first planarization layer is arranged on the driving structurelayer.

The first electrode is arranged on the first planarization layer andconnected with the first thin film transistor in the driving structurelayer through a via hole formed on the first planarization layer.

The pixel definition layer is arranged on the first planarization layerand includes multiple pixel openings, wherein the pixel opening exposesthe first electrode.

The organic light emitting layer is arranged on the first electrode.

The second electrode is arranged on the organic light emitting layer.

The encapsulation layer is arranged on the second electrode and coversthe whole substrate.

The color filter layer is arranged on the encapsulation layer.

In some exemplary embodiments, the orthographic projection of the touchcontrol structure layer on the substrate is located within the range ofthe orthographic projection of the pixel definition layer on thesubstrate.

In some exemplary embodiments, the orthographic projection of the coloroptical filter on the substrate contains the orthographic projection ofthe organic light emitting layer on the substrate.

In some exemplary embodiments, the driving structure layer includes: abuffer layer, an active layer, a first gate insulating layer, a firstgate electrode layer, a second gate insulating layer, a second gateelectrode layer, a first interlayer insulating layer and a first sourceand drain metal layer which are layer stacked arranged on the substratein turn.

In some exemplary embodiments, the display substrate further includes asecond coating protective layer covering the color filter layer and acover plate arranged above the second coating protective layer.

In some exemplary embodiments, the thickness of the second coatingprotective layer is 1.5 microns to 2.5 microns.

In a second aspect, the present disclosure also provides a displayapparatus, including the above display substrate.

In a third aspect, the present disclosure also provides a preparationmethod of a display substrate, which includes: forming multiple pixelunits on a substrate; forming a color filter layer on the pixel unit,wherein the color filter layer includes color optical filters ofdifferent colors and a touch control structure layer arranged betweenthe color optical filters of different colors, the touch controlstructure layer includes a touch control connection electrode, a firstcoating protective layer covering the touch control connection electrodeand a touch control electrode arranged on the first coating protectivelayer, wherein the touch control electrode includes a first touchcontrol electrode and a second touch control electrode, and at least oneof the first touch control electrode and the second touch controlelectrode is connected with the touch control connection electrodethrough a via hole penetrating through the first coating protectivelayer.

In some exemplary embodiments, forming multiple pixel units on thesubstrate includes:

forming a driving structure layer on the substrate;

forming a first planarization layer on the driving structure layer;

forming a first electrode and a pixel definition layer on the firstplanarization layer;

forming an organic light emitting layer on the pixel definition layer;

forming a second electrode on the organic light emitting layer; and

forming an encapsulation layer on the second electrode.

In some exemplary embodiments, forming the color filter layer on thepixel unit includes:

forming a touch control connection electrode on the encapsulation layer,wherein an orthographic projection of the touch control connectionelectrode on the substrate is within a range of an orthographicprojection of the pixel definition layer on the substrate;

forming a first coating protective layer covering the touch controlconnection electrode, and forming a via hole exposing the touch controlconnection electrode on the first coating protective layer;

forming a touch control electrode on the first coating protective layer,wherein the touch control electrode is connected with the touch controlconnection electrode layer through a via hole; and

forming color optical filters of different colors, wherein theorthographic projection of the color optical filters on the substratecontains the orthographic projection of the organic light emitting layeron the substrate.

Other aspects will become apparent upon reading and understandingaccompanying drawings and the detailed description.

BRIEF DESCRIPTION OF DRAWINGS

The attached drawings are for providing a further understanding of thetechnical scheme of the present disclosure and constitute a part of thedescription. They are for explaining the technical scheme of the presentdisclosure together with the embodiments of the present application anddo not constitute a limitation on the technical scheme of the presentdisclosure. Shapes and sizes of the components in the drawings do notreflect true proportions and only to be used to schematically illustratecontents of the present disclosure.

FIG. 1 is a schematic diagram of a structure of a display substrateaccording to an embodiment of the present disclosure.

FIG. 2 a is a schematic diagram of a light out angel of a displaysubstrate.

FIG. 2 b is a schematic diagram of a structure of a light out angel of adisplay substrate according to an exemplary embodiment.

FIG. 3 is a schematic diagram of a display substrate after a pattern ofa flexible substrate is prepared according to an exemplary embodiment.

FIG. 4 is a schematic diagram of a display substrate after a pattern ofa driving structure layer is prepared according to an exemplaryembodiment.

FIG. 5 is a schematic diagram of a display substrate after a pattern ofa first planarization layer is formed according to an exemplaryembodiment.

FIG. 6 is a schematic diagram of a display substrate after a pattern ofa first electrode is formed according to an exemplary embodiment.

FIG. 7 is a schematic diagram of a display substrate after a pattern ofa pixel definition layer is formed according to an exemplary embodiment.

FIG. 8 is a schematic diagram of a display substrate after a pattern ofa second electrode is formed according to an exemplary embodiment.

FIG. 9 is a schematic diagram of a display substrate after a pattern ofan encapsulation layer is formed according to an exemplary embodiment.

FIG. 10 is a schematic diagram of a display substrate after a pattern ofa touch control electrode is formed according to an exemplaryembodiment.

FIG. 11 is a schematic diagram of display substrate after a pattern of afirst coating protective layer is formed according to an exemplaryembodiment.

FIG. 12 is a schematic diagram of a display substrate after a pattern ofa touch control electrode is formed according to an exemplaryembodiment.

FIG. 13 is a schematic diagram of a display substrate after a pattern ofa color optical filter is formed according to an exemplary embodiment.

FIG. 14 is a schematic diagram of a display substrate after a coverplate is attach according to an exemplary embodiment.

FIG. 15 is a flow schematic diagram of a preparation method of a displaysubstrate according to an exemplary embodiment.

DETAILED DESCRIPTION

Specific implementations of the present disclosure will be described indetail below with reference to the accompanying drawings andembodiments. The following embodiments serve to illustrate the presentdisclosure, but are not intended to limit the scope of the presentdisclosure. The embodiments and features in the embodiments in thepresent disclosure may be combined randomly if there is no conflict.

A display substrate structure has problems such as complex process, highcost, small brightness attenuation angle and so on.

The embodiment of the disclosure provides a display substrate, whichincludes a substrate, multiple pixel units arranged on the substrate anda color filter layer arranged on the pixel unit, wherein the colorfilter layer includes color optical filters of different colors and atouch control structure layer arranged between the color optical filtersof different colors; the touch control structure layer includes a touchcontrol connection electrode, a first coating protective layer coveringthe touch control connection electrode and a touch control electrodearranged on the first coating protective layer, wherein the touchcontrol electrode includes a first touch control electrode and a secondtouch control electrode, and at least one of the first touch controlelectrode and the second touch control electrode is connected with thetouch control connection electrode through a via hole penetratingthrough the first coating protective layer.

According to the display substrate provided by the embodiment of thedisclosure, a black matrix (BM) Mask process and a protective layercoating process are omitted by arranging the touch control structurelayer between color optical filters of different colors, so that thepurposes of cost saving and process simplification are achieved, thedistance between the organic light emitting layer and the color filterlayer is shortened, the thickness of the display substrate is reduced,the brightness decay (L-Decay) angle is effectively increased, the powerconsumption is reduced, the preparation process is simple, theproduction efficiency is high, having advantages of low production costand high yield, etc., and having a good application prospect.

FIG. 1 is a schematic diagram of a structure of a display substrateaccording to an embodiment of the present disclosure. As shown in FIG. 1, the display substrate according to an embodiment of the presentdisclosure may include: a substrate 10 and multiple pixel units matrixarranged on the substrate 10. Each pixel unit includes multiplesub-pixels. For example, each pixel unit may include three sub-pixels,namely red sub-pixel R, green sub-pixel G and blue sub-pixel B.

The display substrate may further include a color filter layer arrangedon the pixel unit. The color filter layer may include color opticalfilters 28 of different colors and a touch control structure layerarranged between the color optical filters 28 of different colors. Thetouch control structure layer includes a touch control connectionelectrode 25, a first coating protective layer 26 covering the touchcontrol connection electrode 25, and a touch control electrode 27arranged on the first coating protective layer 26. The touch controlelectrode 27 includes a first touch control electrode and a second touchcontrol electrode, wherein at least one of the first touch controlelectrode and the second touch control electrode is connected with thetouch control connection electrode 25 through a via hole penetratingthrough the first coating protective layer 26.

In this embodiment, by arranging the touch control structure layerbetween color optical filters of different colors, the distance betweenthe organic light emitting layer and the color filter layer is shortened(in an exemplary embodiment, the distance is shortened by about 18%),and the thickness of the display substrate is reduced (in an exemplaryembodiment, the thickness is reduced by about 56%). As shown in FIG. 2 ato FIG. 2 b and table 1, FIG. 2 a shows a schematic diagram of the lightout angle of structure I, wherein structure I refers to a displaysubstrate with the touch control structure layer arranged between theorganic light emitting layer and the color filter layer. Under thecondition of color optical filters of the same width, compared withstructure I, the display substrate of this embodiment increases thelight out angle of the organic light emitting layer, that is, the lightdecay L-Decay angle is increased efficiently, the power consumption isreduced, being beneficial to realize the bending function.

TABLE 1 Light out angle of The light out angle of the structure of thestructure I present disclosure R α = 42.0° α 1 = 47.7 (α 1 is increasedby 13.6% compared with α) G β = 53.2° β 1 = 58.4 (β 1 is increased by9.8% compared with β) B γ = 61.4° γ 1 = 65.9 (γ 1 is increased by 7.3%compared with γ)

In an exemplary embodiment, as shown in FIG. 1 , the touch controlelectrode 27 may include a first metal layer 27 a and a second metallayer 27 b arranged on the first metal layer 27 a. An orthographicprojection of the second metal layer 27 b on the substrate 10 coincideswith an orthographic projection of the first metal layer 27 a on thesubstrate 10.

The second metal layer 27 b is directly arranged on the first metallayer 27 a, so that widths of the first metal layer 27 a and the secondmetal layer 27 b may be set as a width of an opening between the coloroptical filters, and the first metal layer 27 a does not reflect light,which increases the width of the touch control electrode 27 and reducesa wiring resistance of the touch control electrode 27.

In an exemplary embodiment, a reflectivity of the second metal layer 27b may be less than a first reflectivity.

In an exemplary embodiment, the first reflectivity may be 17%.

In an exemplary embodiment, a material of the second metal layer 27 bmay be molybdenum oxide (MoOx) or other materials with a lowreflectivity. The thickness of the second metal layer 27 b may be 35 nmto 75 nm. The reflectivity of molybdenum oxide (MoOx) in differentthickness ranges is shown in table 2.

TABLE 2 Material BM MoOx Thickness range 1.0 μm to 1.5 μm 35 nm to 75 nmReflectivity range 0.074 to 0.057 0.173 to 0.039

In an exemplary embodiment, MoOx is black under illumination and has alow reflectivity. Setting a surface layer of the touch control electrode27 as MoOx may reduce a reflectivity of a black matrix (BM) in a CF onEncapsulation (COE).

In an exemplary embodiment, the touch control electrode 27 may furtherinclude a third metal layer, a first metal layer arranged on the thirdmetal layer, and a second metal layer arranged on the first metal layer.The third metal layer can protect the first metal layer.

In an exemplary embodiment, a material of the third metal layer may betitanium (Ti).

In an exemplary embodiment, a material of the first metal layer may bealuminum (Al).

In an exemplary embodiment, a material of the second metal layer may bemolybdenum oxide (MoOx).

In an exemplary embodiment, the thickness of the touch control electrode27 may be 300 nm to 400 nm.

In an exemplary embodiment, the thickness of the color filter layer maybe 2 microns to 3 microns.

In an exemplary embodiment, the thickness of the touch controlconnection electrode may be 150 nm to 300 nm.

In an exemplary embodiment, the thickness of the first coatingprotective layer may be 1.5 microns to 2.5 microns.

In an exemplary embodiment, each sub-pixel includes a driving structurelayer, a first planarization layer 19, a first electrode 20, a pixeldefinition layer 21, an organic light emitting layer 22, a secondelectrode 23 and an encapsulation layer 24.

The driving structure layer is arranged on the substrate 10, wherein adriving structure layer in each sub-pixel includes a first thin filmtransistor.

The first planarization layer 19 is arranged on the driving structurelayer.

The first electrode 20 is arranged on the first planarization layer 19and connected with the first thin film transistor in the drivingstructure layer through a via hole formed in the first planarizationlayer 19.

The pixel definition layer 21 is arranged on the first planarizationlayer 19, and includes multiple pixel openings, wherein the pixelopening exposes the first electrode 20.

The organic light emitting layer 22 is arranged on the first electrode20.

The second electrode 23 is arranged on the organic light emitting layer22.

The encapsulation layer 24 is arranged on the second electrode layer 23and covers a whole substrate 10.

The color filter layer is arranged on the encapsulation layer 24.

In an exemplary embodiment, the orthographic projection of the touchcontrol structure layer on the substrate 10 is located within the rangeof the orthographic projection of the pixel definition layer 21 on thesubstrate 10.

In an exemplary embodiment, the orthographic projection of the coloroptical filter 28 on the substrate 10 contains the orthographicprojection of the organic light emitting layer 22 on the substrate 10.

In an exemplary embodiment, the display substrate may further include: asecond coating protective layer 29 covering the color filter layer and acover plate 31 arranged above the second coating protective layer 29.

In an exemplary embodiment, the thickness of the second coatingprotective layer 29 is 1.5 microns to 2.5 microns.

In an exemplary embodiment, as shown in FIG. 1 , the driving structurelayer may include: a buffer layer 11, an active layer 12, a firstinsulating layer 13, a first gate electrode layer, a second insulatinglayer 15, a second gate electrode layer 16, a first interlayerinsulating layer 17, and a source and drain metal layer which are layerstacked arranged on the substrate 10 in turn.

The technical scheme of the display substrate according to an exemplaryembodiment will be described as following through the preparationprocess of the display substrate. A “patterning process” mentioned inthe embodiment includes processes, such as a film layer deposition, aphotoresist coating, a mask exposure, a development, an etching, and aphotoresist stripping, etc. A “photoetching process” mentioned in theembodiment includes processes, such as a film layer coating, a maskexposure, and a development, etc. Any one or more selected fromsputtering, evaporation and chemical vapor deposition may be used fordeposition. Any one or more selected from spray coating and spin coatingmay be used for coating. Any one or more selected from dry etching andwet etching may be used for etching. A “thin film” refers to a layer ofthin film manufactured by deposition or coating of a certain material ona substrate base. If the “thin film” does not need to be subjected to apatterning process during the whole manufacturing process, a “thin film”may also be called a “layer”. When the “thin film” needs to be subjectedto a patterning process during the whole manufacturing process, a “thinfilm” is referred to as a “thin film” prior to the patterning processand as a “layer” subsequent to the patterning process. The “layer”subsequent to the patterning process contains at least one “pattern”. Inthe present disclosure, “a and b are arranged on the same layer” meansthat a and b are formed at the same time by the same patterning process.“An orthographic projection of A contains an orthographic projection ofB” means that the orthographic projection of B falls within the scope ofthe orthographic projection of A, or the orthographic projection of Acovers the orthographic projection of B.

(1) A flexible substrate base 10 is prepared on a glass carrier plate 1.

In an exemplary embodiment, a material of the flexible substrate 10 mayadopt a material such as polyimide (PI), polyethylene terephthalate(PET), or a surface-treated polymer soft film, etc., as shown in FIG. 3.

(2) A pattern of the driving structure layer is prepared on the flexiblesubstrate 10. The driving structure may include multiple gate lines andmultiple data lines. The multiple gate lines and the multiple data linesvertically cross to define multiple sub-pixels which are matrixarranged. Each pixel unit includes at least three sub-pixels, and eachsub-pixel includes at least one first Thin Film Transistor (TFT).

In an exemplary embodiment, the first thin film transistor may be of abottom gate structure or a top gate structure, which is not limitedherein.

In an exemplary embodiment, the first thin film transistor may be anAmorphous Silicon (a-Si) thin film transistor, a low-temperaturepolysilicon (LTPS) thin film transistor or an oxide thin filmtransistor, which is not limited herein.

In an exemplary embodiment, a pixel unit may include three sub-pixels, ared sub-pixel R, a green sub-pixel G and a blue sub-pixel Brespectively. Or a pixel unit may include four sub-pixels, a redsub-pixel R, a green sub-pixel G, a blue sub-pixel B and a whitesub-pixel W.

In an exemplary embodiment, the preparation process of the drivingstructure layer may include: depositing a first insulating thin film andan active layer thin film on the flexible substrate 10 in turn andpatterning the active layer thin film through a patterning process toform a first insulating layer 11 covering a whole flexible base 10 and apattern of an active layer 12 on the first insulating layer 11. Thefirst insulating layer 11 is called a buffer layer, which is configuredto improve the water and oxygen resistance of the substrate.

Then, a second insulating thin film and a first metal thin film aredeposited in turn, and the first metal thin film is patterned through apatterning process to form a second insulating layer 13 covering thepattern of the active layer 12 and a pattern of a first gate metal layerarranged on the second insulating layer 13, wherein the first gateelectrode layer at least include a first gate electrode 14 a, a firstcapacitor electrode 14 b, multiple gate lines (not shown) and multiplegate leads (not shown). The second insulating layer 13 is called a firstgate insulating (GI1) layer.

Then, a third insulating thin film and a second metal thin film aredeposited in turn, and the second metal thin film is patterned through apatterning process to form a third insulating layer 15 covering thefirst gate electrode layer 14 and a pattern of a second gate electrodelayer arranged on the third insulating layer 15, wherein the second gateelectrode layer at least include a second capacitor electrode 16 and asecond gate lead (not shown), and a position of the second capacitorelectrode 16 corresponds to a position of the first capacitor electrode14 b. The third insulating layer 15 is also called a second gateinsulting (GI2) layer.

Then, a fourth insulating thin film is deposited and patterned through apatterning process to form a pattern of a fourth insulating layer 17covering the second gate electrode layer, wherein the fourth insulatinglayer 17 is provided with multiple first via holes, positions of themultiple first via holes correspond positions of both ends of the firstactive layer respectively, the fourth insulating layer 17, the thirdinsulating layer 15 and the second insulating layer 13 in the first viahole are etched to expose the surface of the first active layer. Thefourth insulating layer 17 is also called a first interlayer insulating(ILD) layer.

Then, a third metal thin film is deposited, the third metal thin film ispatterned through a patterning process to form a pattern of a source anddrain metal layer on the fourth insulating layer 17, wherein the sourceand drain metal layer at least include patterns of a first sourceelectrode 18 a, a first drain electrode 18 b, low voltage (VSS) line(not shown), multiple data lines (not shown) and multiple data leads(not shown), the first source electrode 18 a and the first drainelectrode 18 b are connected through a first via hole and active layer12. The source and drain metal layer may also include any one or more ofa power supply line (VDD), a compensation line and an auxiliary secondelectrode, and the source and drain metal layer is also called a firstsource and drain metal layer (SD1).

At this point, the driving structure layer pattern is prepared on theflexible substrate 10, which is as shown in FIG. 4 . The active layer12, the first gate electrode 14 a, the first source electrode 18 a andthe first drain electrode 18 b constitute a first thin film transistor.The first capacitor electrode 14 b and the second capacitor electrode 16b constitute a first storage capacitor. Multiple gate leads and dataleads constitute the driving leads of Gate Driver on Array (GOA).

(3) A first flat thin film is coated on the flexible substrate on whichthe aforementioned pattern is formed to form a first planarization (PLN)layer 19 covering a whole flexible substrate 10, a second via hole isformed on the first planarization layer 19 through a patterning process,wherein the first planarization layer 19 in the second via hole isetched away to expose a surface of a first drain electrode of the firstthin film transistor, as shown in FIG. 5 .

(4) A transparent conductive thin film is deposited on the substrate onwhich the aforementioned pattern is formed, and the transparentconductive thin film is patterned through a patterning process to form apattern of a first electrode 20, wherein the first electrode 20 isconnected with a first drain electrode D through the second via hole.Forming the pattern of the first electrode 20 includes: depositing afourth metal thin film on the substrate on which the aforementionedpattern is formed, coating a layer of photoresist on the fourth metalthin film, exposing the photoresist with a single tone mask, forming anunexposed area at a position where the first electrode 20 is located,forming a completely exposed area at other positions, developing andremoving the photoresist at the completely exposed area, then etchingthe fourth metal thin film at the completely exposed area and strippingthe remaining photoresist to form the pattern of the first electrode 20,as shown in FIG. 6 . Since the display substrate of this embodiment is atop emission structure, the first electrode 20 is a reflective electrodeand may adopt metals with high reflectivity, such as silver Ag, gold Au,palladium Pd, platinum Pt, etc., or alloys of these metals, or compositelayers of these metals. In practice, a composite layer structure ofindium tin oxide ITO layer and metal reflective layer may also beadopted, which has good conductivity, high reflectivity and goodmorphological stability.

(5) A pixel definition thin film is coated on the substrate on which theaforementioned pattern is formed, and a pattern of a pixel definitionlayer (PDL) 21 is formed through masking, exposure and developmentprocesses, wherein the pixel definition layer 21 is provided thereonwith a pixel opening, and a pixel definition thin film within the pixelopening is developed away to expose a surface of the first electrode 20.The pixel definition layer 21 is provided thereon with a first opening,wherein a pixel definition thin film in the pixel opening is developedaway to expose a surface of the first planarization layer 19, as shownin FIG. 7 .

(6) An organic light emitting layer 22 and a second electrode 23 areformed in turn on the substrate on which the aforementioned pattern isformed, as shown in FIG. 8 . The organic light emitting layer 22includes a hole injection layer, a hole transmission layer, a lightemitting layer, an electron transporting layer and an electron injectionlayer which are stacked arranged, to realize that the organic lightemitting layer 22 and the first electrode 20 are connected within thepixel opening. Since the first 20 is connected with the first drainelectrode D of the first transistor, light emission control of theorganic light emitting layer 22 is achieved. The second electrode 23 isconnected with the organic light emitting layer 22.

(7) A pattern of the encapsulation layer 24 is formed on the substrateon which the aforementioned pattern is formed. As shown in FIG. 9 , theencapsulation layer 24 may adopt a stacked structure of inorganicmaterial/organic material/inorganic material, and the organic materiallayer is arranged between the two inorganic material layers.

(8) A pattern of the touch control connection electrode 25 is formed onthe substrate on which the aforementioned pattern is formed. As shown inFIG. 10 , the orthographic projection of the touch control connectionelectrode 25 on the substrate is within a range the orthographicprojection of the pixel definition layer 21 on the substrate. Thethickness of the touch control connection electrode is about 150 nm to300 nm.

(9) A pattern of the first coating protective layer 26 is formed on thesubstrate on which the aforementioned pattern is formed. As shown inFIG. 11 , the first coating protective layer 26 is provided withmultiple via holes, wherein the via hole exposes a surface of the touchcontrol connection electrode 25. The thickness of the first coatingprotective layer 26 is about 1.5 microns to 2.5 microns.

(10) A pattern of the touch control electrode 27 is formed on thesubstrate on which the aforementioned pattern is formed. As shown inFIG. 12 , the thickness of the touch control electrode 27 is about 3000Amy to 4000 Amy, wherein the touch control electrode 27 may be made ofmultilayer metal of Ti/Al/MoOx, the thickness of MoOx is about 35 nm to70 nm. In addition, because a surface layer MoOx of the touch controlelectrode 27 is black under illumination and has low reflectivity, thesurface layer MoOx may play a reflectivity reduction role of a blackmatrix in a color resistance structure.

(11) Patterns of color optical filters 28 of different colors are formedon the substrate on which the aforementioned pattern is formed, as shownin FIG. 13 . Forming the pattern of the color optical filter layerincludes: coating a polymer photoresist layer mixed with red pigment onthe encapsulation layer 24, exposing and developing to form a pattern ofa red area; using the same method and steps to form a pattern of a greenarea and a pattern of a blue area in turn, and forming a color opticalfilters 28 of red, green and blue arranged according to certain rules.The thickness of the color optical filter 28 is about 2 microns to 3microns.

(12) A thin film encapsulation process is performed on the substrate onwhich the aforementioned pattern is formed to form a pattern of a secondcoating protective layer 29; an optical glue 30 is coated on thesubstrate on which the pattern of the second coating protective layer 29is formed, and a cover plate 31 is attach to the optical glue 30, asshown in FIG. 14 . The thickness of the second coating protective layeris about 1.5 microns to 2.5 microns.

(13) After the above film layer structure is prepared, the displaysubstrate is peeled off from the glass carrier board 1 by a peelingprocess, and then a layer of base film 2 is attached to the back of thedisplay substrate (a surface of the flexible substrate 10 on a side awayfrom the film layer) by using roller attaching, a fingerprintidentification sensor 32 is attached to a surface of the base film 2 ona side away from the flexible substrate 10 through a foam layer 33,wherein the fingerprint identification sensor 32 is connected with theflexible printed circuit (FPC) 34, as shown in FIG. 1 .

Through the above processes, the preparation of the display substrateshown in FIG. 1 is completed. It can be seen from the above preparationprocess that the display substrate provided by this embodiment omits aBM Mask process and a protective layer coating process by arranging thetouch control structure layer between color optical filters of differentcolors, thereby achieving the purposes of saving costs and simplifyingprocesses, shortening the distance between the organic light emittinglayer and the color filter layer, reducing the thickness of the displaysubstrate, effectively increasing the brightness attenuation angle, andreducing power consumption. The preparation process is simple, theproduction efficiency is high, having the advantages low production costand high yield and the like, and having a good application prospect.

Although the display substrate of this embodiment is described as a topemission structure, the scheme of this embodiment is also applicable toa bottom emission structure or a double-sided emission structure, and isalso applicable to large-sized or small-sized display substrates. Asshown in FIG. 1 , a display substrate prepared through above preparationprocess includes: a substrate 10, a driving structure layer, a firstplanarization layer 19, a light emitting structure layer, anencapsulation layer 24, a color filter layer, a second coatingprotective layer 29, a cover plate 31, a base film 2, and a fingerprintidentification sensor 32.

The driving structure layer is arranged on the substrate 10, and adriving structure layer in each sub-pixel includes a first thin filmtransistor.

The first planarization layer 19 is arranged on the driving structurelayer.

The light emitting structure layer is arranged on the firstplanarization layer 19, a light emitting structure layer in eachsub-pixel includes a first electrode 20, a pixel definition layer 21, anorganic light emitting layer 22 and a second electrode 23, the firstelectrode 20 is arranged on the first planarization layer 19 andconnected with the first thin film transistor in the driving structurelayer through a via hole formed in the first planarization layer 19, thepixel definition layer 21 is arranged on the first planarization layer19 and includes multiple pixel openings, the pixel opening exposes thefirst electrode, the organic light emitting layer 22 is arranged on thefirst electrode 20, and the second electrode 23 is arranged on theorganic light emitting layer 22.

The encapsulation layer 24 is arranged on the second electrode layer 23,wherein the encapsulation layer 24 covers a whole display substrate.

The color filter layer is arranged on the encapsulation layer 24, colorfilter layer includes color optical filters 28 of different colors and atouch control structure layer arranged between the color optical filters28 of different colors, the touch control structure layer includes atouch control connection electrode 25, a first coating protective layer26 covering the touch control connection electrode 25, and a touchcontrol electrode 27 arranged on the first coating protective layer 26,the touch control electrode 27 includes a first touch control electrodeand a second touch control electrode, at least one of the first touchcontrol electrode and the second touch control electrode is connectedwith the touch control connection electrode 25 through a via holepenetrating the first coating protective layer 26.

The second coating protective layer 29 is arranged on the color filterlayer for protecting the color filter layer.

The cover plate 31 is attached to the second coating protective layer 29through an optical glue 30.

The base film 2 is arranged on a surface of the substrate 10 on a sideaway from the driving structure layer.

The fingerprint identification sensor 32 is attached to a surface of thebase film 2 on a side away from the substrate 10.

The present disclosure further provides a method for preparing a displaysubstrate. As shown in FIG. 15 , a method for preparing a displaysubstrate provided by an embodiment of the present disclosure mayinclude steps S1 and S2.

Step S1 includes forming multiple pixel units on the substrate.

Step S2 includes forming a color filter layer on the pixel unit, whereinthe color filter layer includes color optical filters of differentcolors and a touch control structure layer arranged between the coloroptical filters of different colors, the touch control structure layerincludes a touch control connection electrode, a first coatingprotective layer covering the touch control connection electrode and atouch control electrode arranged on the first coating protective layer,the touch control electrode includes a first touch control electrode anda second touch control electrode, and at least one of the first touchcontrol electrode and the second touch control electrode is connectedwith the touch control connection electrode through a via holepenetrating the first coating protective layer.

In an exemplary embodiment, forming the multiple pixel units on thesubstrate includes:

forming a driving structure layer on the substrate;

forming a first insulating film on a first planarization layer on thedriving structure layer;

forming a first electrode and a pixel definition layer on the firstplanarization layer;

forming an organic light emitting layer on the pixel definition layer;

forming a second electrode on the organic light emitting layer; and

forming an encapsulation layer on the second electrode.

In an exemplary embodiment, forming a color filter layer on a pixel unitmay include:

forming a touch control connection electrode on the encapsulation layer,wherein an orthographic projection of the touch control connectionelectrode on the substrate is within a range of an orthographicprojection of the pixel definition layer on the substrate;

forming a first coating protective layer covering the touch controlconnection electrode on the touch control connection electrode, andforming a via hole exposing the connection electrode on the firstcoating protective layer;

forming a touch control electrode on the first coating protective layer,wherein the touch control electrode layer is connected with the touchcontrol connection electrode layer through a via hole; and

forming color optical filters of different colors, wherein anorthographic projection of the color optical filters on the substratecontains an orthographic projection of the organic light emitting layeron the substrate.

In an exemplary embodiment, the touch control electrode may include afirst metal layer and a second metal layer arranged on the first metallayer. An orthographic projection of the second metal layer on thesubstrate coincides with an orthographic projection of the first metallayer on the substrate, and a reflectivity of the second metal layer isless than a first reflectivity.

In an exemplary embodiment, a material of the second metal layer may bemolybdenum oxide (MoOx) or other materials with low reflectivity, athickness of the second metal layer may be 35 nm to 75 nm, and the firstreflectivity may be 17%.

In an exemplary embodiment, a thickness of the touch control electrodemay be 300 microns to 400 microns.

In an exemplary embodiment, a thickness of the color filter layer may be2 microns to 3 microns, a thickness of the touch control connectionelectrode may be 150 nm to 300 nm, and a thickness of the first coatingprotective layer may be 1.5 microns to 2.5 microns.

According to the preparation method of the display substrate provided bythis embodiment, by arranging the touch control structure layer betweenthe color optical filters of different colors, a BM Mask process and aprotective layer coating process are omitted, so that the purposes ofcost saving and process simplification are achieved, the distancebetween the organic light emitting layer and the color filter layer isshortened, the thickness of the display substrate is reduced, thebrightness attenuation angle is effectively increased, the powerconsumption is reduced, the preparation process is simple, theproduction efficiency is high, having the advantages of low productioncost, high yield and the like and a good application prospect.

An embodiment of the present disclosure further provides a displayapparatus which includes display substrates of aforementionedembodiments. The display apparatus may be any product or component witha display function such as a mobile phone, a tablet computer, atelevision, a display, a laptop computer, a digital photo frame, anavigator, etc.

In the description of embodiments of the present disclosure, orientationor positional relationships indicated by terms “middle”, “upper”,“lower”, “front”, “back”, “vertical”, “horizontal”, “top”, “bottom”,“inside”, “outside” and the like are based on the orientation orpositional relationships shown in the drawings, and are for ease ofdescription of the present disclosure and simplification of thedescription only, but are not intended to indicate or imply that thementioned device or element must have a specific orientation, or beconstructed and operated in a particular orientation, and therefore theyshould not be construed as limitation to the present disclosure.

In the description of embodiments of the present disclosure, unlessotherwise clearly specified and defined, the terms “install”, “connect”,“couple” should be broadly interpreted, for example, it may be connectedfixedly or connected detachably, or integrated; it may be a mechanicalconnection or an electrical connection; it may be directly connected, ormay be indirectly connected through an intermediary, or may be aninternal connection between two elements. Those of ordinary skill in theart can understand the meanings of the above mentioned terms in thepresent disclosure.

Although the embodiments disclosed in the present disclosure are asdescribed above, the described contents are only the embodiments forfacilitating understanding of the present disclosure, which are notintended to limit the present disclosure. Any person skilled in the artto which the present disclosure pertains may make any modifications andvariations in the form and details of implementation without departingfrom the spirit and scope of the present disclosure. Nevertheless, thescope of patent protection of the present disclosure shall still bedetermined by the scope defined by the appended claims.

What we claim is:
 1. A display substrate, comprising: a substrate,multiple pixel units arranged on the substrate and a color filter layerarranged on the pixel unit, wherein: the color filter layer comprisescolor optical filters of different colors and a touch control structurelayer arranged between the color optical filters of different colors;and the touch control structure layer comprises a touch controlconnection electrode, a first coating protective layer covering thetouch control connection electrode and a touch control electrodearranged on the first coating protective layer, the touch controlelectrode comprises a first touch control electrode and a second touchcontrol electrode, and at least one of the first touch control electrodeand the second touch control electrode is connected with the touchcontrol connection electrode through a via hole penetrating through thefirst coating protective layer.
 2. The display substrate of claim 1,wherein the touch control electrode comprises a first metal layer and asecond metal layer arranged on the first metal layer, and anorthographic projection of the first metal layer on the substratecoincides with an orthographic projection of the second metal layer onthe substrate.
 3. The display substrate of claim 2, wherein the touchcontrol electrode further comprises: a third metal layer, wherein thefirst metal layer is arranged on the third metal layer, and amanufacturing material of the third metal layer comprises titanium. 4.The display substrate of claim 2, wherein a reflectivity of the secondmetal layer is less than a first reflectivity, and a manufacturingmaterial of the third metal layer comprises molybdenum oxide.
 5. Thedisplay substrate of claim 4, wherein the first reflectivity is 17%. 6.The display substrate of claim 1, wherein a thickness of the touchcontrol electrode is 300 nm to 400 nm.
 7. The display substrate of claim2, wherein a thickness of the second metal layer is 35 microns to 70microns.
 8. The display substrate of claim 1, wherein a thickness of thecolor filter layer is 2 microns to 3 microns.
 9. The display substrateof claim 1, wherein a thickness of the touch control connectionelectrode is 150 nm to 300 nm.
 10. The display substrate of claim 1,wherein a thickness of the first coating protective layer is 1.5 micronsto 2.5 microns.
 11. The display substrate of claim 1, wherein the pixelunit comprises multiple sub-pixels, and each sub-pixel comprises adriving structure layer, a first planarization layer, a first electrode,a pixel definition layer, an organic light emitting layer, a secondelectrode and an encapsulation layer, wherein: the driving structurelayer is arranged on the substrate, and a driving structure layer ineach sub-pixel comprises a first thin film transistor; the firstplanarization layer is arranged on the driving structure layer; thefirst electrode is arranged on the first planarization layer andconnected with the first thin film transistor in the driving structurelayer through a via hole formed on the first planarization layer; thepixel definition layer is arranged on the first planarization layer andcomprises multiple pixel openings, and the pixel opening expose thefirst electrode; the organic light emitting layer is arranged on thefirst electrode; the second electrode is arranged on the organic lightemitting layer; the encapsulation layer is arranged on the secondelectrode and covers the whole substrate; and the color filter layer isarranged on the encapsulation layer.
 12. The display substrate of claim11, wherein an orthographic projection of the touch control structurelayer on the substrate is within a range of an orthographic projectionof the pixel definition layer on the substrate.
 13. The displaysubstrate of claim 11, wherein an orthographic projection of the coloroptical filter on the substrate contains an orthographic projection ofthe organic light emitting layer on the substrate.
 14. The displaysubstrate of claim 11, wherein the driving structure layer comprises abuffer layer, an active layer, a first gate insulating layer, a firstgate electrode layer, a second gate insulating layer, a second gateelectrode layer, a first interlayer insulating layer and a first sourceand drain metal layer which are layer stacked on the substrate in turn.15. The display substrate of claim 1, further comprising a secondcoating protective layer covering the color filter layer and a coverplate arranged above the second coating protective layer.
 16. Thedisplay substrate of claim 15, wherein a thickness of the second coatingprotective layer is 1.5 microns to 2.5 microns.
 17. A display apparatus,comprising the display substrate of claim
 1. 18. A preparation method ofa display substrate, comprising: forming multiple pixel units on asubstrate; forming a color filter layer on the pixel unit, wherein thecolor filter layer comprises color optical filters of different colorsand a touch control structure layer arranged between the color opticalfilters of different colors, the touch control structure layer comprisesa touch control connection electrode, a first coating protective layercovering the touch control connection electrode and a touch controlelectrode arranged on the first coating protective layer, the touchcontrol electrode comprises a first touch control electrode and a secondtouch control electrode, and at least one of the first touch controlelectrode and the second touch control electrode is connected with thetouch control connection electrode through a via hole penetratingthrough the first coating protective layer.
 19. The method of claim 18,wherein the forming multiple pixel units on the substrate comprises:forming a driving structure layer on the substrate; forming a firstplanarization layer on the driving structure layer; forming a firstelectrode and a pixel definition layer on the first planarization layer;forming an organic light emitting layer on the pixel definition layer;forming a second electrode on the organic light emitting layer; andforming an encapsulation layer on the second electrode.
 20. The methodof claim 19, wherein, forming the color filter layer on the pixel unitcomprises: forming a touch control connection electrode on theencapsulation layer, wherein an orthographic projection of the touchcontrol connection electrode on the substrate is within a range of anorthographic projection of the pixel definition layer on the substrate;forming a first coating protective layer covering the touch controlconnection electrode, and forming a via hole exposing the touch controlconnection electrode on the first coating protective layer; forming atouch control electrode on the first coating protective layer, whereinthe touch control electrode is connected with the touch controlconnection electrode layer through a via hole; and forming color opticalfilters of different colors, wherein an orthographic projection of thecolor optical filter on the substrate contains an orthographicprojection of the organic light emitting layer on the substrate.